1. Field of the Invention
The present invention relates to a coil component, and more particularly to a winding-type coil component.
2. Related Background Art
Known such coil components comprise a core (so-called drum-type core) having a winding core portion and a pair of flanges arranged at both ends of the winding core portion, a winding wound on the winding core portion, and a cladding resin containing a magnetic powder, filling the space between the pair of flanges (for instance, Japanese Unexamined Patent Application Laid-open No. 2005-210055). The cladding resin containing a magnetic powder covers the winding at a position between the pair of flanges.
In the coil component described in Japanese Unexamined Patent Application Laid-open No. 2005-210055, the flux generated by the coil formed by the winding constitutes a magnetic circuit that extends from the winding core portion, via one flange, the cladding resin containing a magnetic powder, and the other flange, to return to the winding core portion. In such a magnetic circuit, the cladding resin containing a magnetic powder comes into contact with the pair of flanges. The magnetic circuit is thus is a closed magnetic circuit the entire path whereof traverses portions having magnetism. A closed magnetic circuit configuration allows achieving good inductance characteristics by keeping small the flux leaking from the magnetic circuit (leakage flux). A closed magnetic circuit, however, is problematic in that magnetic saturation is likely to occur in the circuit, impairing DC bias characteristics.